Digestion and Nutrition
Ruminant digestive system
• Mouth- bites and chews food
• Rumen- large part of ruminant’s
stomach where bacteria change
large amounts of roughages into
amino acids
Ruminant digestive system
• Reticulum- the part of the ruminant
stomach where liquids go
• Omasum- grinds and squeezes
feed and removes 60-70% of the
liquid
Ruminant digestive system
• Abomasum- true stomach where
liquids go
• Small intestine- partially digested feed
is mixed with bile, pancreatic juice, and
intestinal juice. Most food nutrients are
absorbed from the villi in the small
intestine
Ruminant digestive system
• Large intestine- main function is to
absorb water and to add mucus to the
undigested feed, which is feces
• Esophagus- connects the mouth to the
stomach
• A ruminant has a 4 part stomach, but
the rumen and reticulum take up about
85% of the capacity
Ruminant digestive system
http://asnet.tamu.edu/w
ww/kids/rumen.htm
Ruminant microbes
http://commtechlab.msu.edu/sites/
dlc-me/zoo/zac0278.html
Non-ruminant digestive system
• Mouth
• Esophagus
• Stomach- enzymes act on feed, churns and
mixes feed
• Small intestine- partially digested feed is
mixed with bile, pancreatic juice, and
intestinal juice. Most food nutrients are
absorbed from the villi in the small intestine
Non-ruminant digestive system
• Liver- produces bile that acts on fats
• Large intestine- absorbs water and adds
mucus to the undigested feed, which is
feces
• Anus- end of tract
• Non-ruminants cannot eat and digest as
much roughage as ruminants
Non-ruminant
http://gened.emc.maricopa.edu/bio/bi
o181/BIOBK/BioBookDIGEST.html
Poultry digestive system
• Mouth- pecks because poultry have
NO teeth
• Esophagus- connects mouth to
crop
• Crop- stores feed
Poultry digestive system
• Gizzard- crushes and mixes feed
with digestive juices, usually
contains grit and gravel to assist in
crushing feed particles
• Liver- produces bile that acts on
fats
Poultry digestive system
• Small intestine- mixes juices and most food
nutrient absorption occurs
• Large intestine- absorbs water and adds
mucus to undigested feed, which is feces
• Vent- anus where both solid wastes (feces)
and liquid wastes (urine) pass out of the
body
• Poultry digestive system has several special
features because poultry have no teeth
Poultry digestive system
http://www.ahsc.ar
izona.edu/uac/iacu
c/poultry/species.s
html
Appearance and location of parts
• Mouth- opening to digestive system on
animal’s head
• Esophagus- tube-like structure that
connects mouth to stomach or to crop in
poultry
• Stomach- storage chamber for mixing and
digesting feed
• Rumen- the largest compartment of a
ruminant’s stomach
Appearance and location of parts
• Liver- dark brown, lobed organ beneath the
stomach or crop
• Small intestine- long tube with partially
digested feed in it
• Large intestine- large, relatively short
compartment with feces in it
• Anus (or vent in poultry)- the outside
opening on the rear end of an animal where
waste leaves the animal
Groups of nutrients
• Carbohydrates- main energy nutrients
• Made up of sugars, starches, cellulose,
and lignin
• Found in the greatest quantities in
livestock feed
• Chemically composed of carbon,
hydrogen, and oxygen
Groups of nutrients
• Fats and oils- 2.25 times the energy
value of carbohydrates
• At body temperature, fats are solids
and oils are liquid
• They carry the fat-soluble vitamins
• Extra carbohydrates are stored as fat
• Composed of carbon, hydrogen, and
oxygen
Groups of nutrients
• Proteins- organic compounds made
up of amino acids
• Contain carbon, hydrogen, oxygen
and nitrogen and sometimes sulfur,
phosphorus, and/or iron
Groups of nutrients
• Vitamins- trace organic compounds
• All contain carbon
• Minerals- inorganic materials or
compounds needed in small
amounts, no carbon
Group of nutrients
• Water- makes up 40-80% of an
animal’s body
Functions of nutrients
• Carbohydrates- provide energy
• Fats and oils- furnish 2.25 times the
energy value of carbohydrates and
carry fat soluble vitamins
• Proteins- supply material to build body
tissues such as muscles, skin and hair
Functions of nutrients
• Vitamins- help regulate many body
functions and are designated by
letters: A, B, C, D, E, K
• Minerals: provide material for growth of
bones, teeth and body tissue and
regulates many of the vital chemical
body processes
Functions of nutrients
• Water- helps dissolve other
nutrients and carry them to different
parts of the body
Sources of nutrients
• Carbohydrates: cereal grains such
as corn, wheat, oats, rye, barley,
and sorghum
• Fats and Oils: grains and protein
concentrates
Sources of nutrients
• Proteins: plant sources include
soybean meal, cottonseed meal,
alfalfa meal, and animal sources
include meat meal, fish meal, dried
milk and synthetic nitrogen source
of urea
Sources of nutrients
• Vitamins and Minerals: most feed
ingredients, pre-mixes are added to
feed
• Water: usually supplied separated
from other nutrients, liquid form
Specific feed sources
• Carbohydrates: corn is most commonly
used in US
• Fats and oils: regular feed ingredients
• Proteins: animal sources: fish meal,
meat meal plant sources: soybean
meal, cottonseed meal
Specific feed sources
•
•
•
•
Vitamins: pre-mix
Minerals: pre-mix and mineral blocks
Water: plumbing, wells
For ruminants, alfalfa hay provides
some energy and high fiber. Molasses
can be added to improve taste
(palatability) and reduce feed dust
The end